1. Field of the Invention
This invention relates to a portable computer which has a hard disk drive mounted therein, more particularly to a removable hard disk drive unit for a portable computer.
2. Description of the Related Art
Referring to FIG. 1, a conventional hard disk drive consists of a disk cartridge (3) and a housing (4). The disk cartridge (3) includes a magnetic head, a spindle motor and an actuator, which are not shown. A printed circuit (not shown) is disposed in the housing (4). The disk cartridge (3) further includes a resilient projection (30) engaged within the hole (40) of the housing (4) so as to retain the disk cartridge (3) in the housing (4) in such a manner that the connector (31) is coupled with the connector (41) of the housing (4). When the disk cartridge (3) is removed from or inserted into the housing (4), the interengaging surfaces thereof wear inevitably, thereby causing the eventual separation of the cartridge (3) from the housing (4) after a long period of usage. Furthermore, in order to withdraw the disk cartridge (3) from the housing (4), a large amount of pull force must be applied to the disk cartridge (3) so as to overcome the spring force of the resilient projection (30).
Referring to FIG. 2, another conventional hard disk drive consists of a disk cartridge (5) and a housing (6). The connector (50) of the disk cartridge (5) is coupled with the connector (60) of the housing (6). The disk cartridge (5) includes two resilient projections (51) extending from two opposite side walls thereof to engage within two retaining holes (61) of the housing (6). When the disk cartridge (5) is removed from or placed into the housing (6), the interengaging surfaces of the connectors (50, 60) easily wear. Furthermore, in order to remove the disk cartridge (5) from the housing (6), it is necessary for the operator to exert on the disk cartridge (5) a pull force which is large enough to overcome the spring force of the resilient projections (51).
Another hard disk drive unit has been screwed to a portable computer which has a central processing unit and a monitor unit laying on and mounted pivotally on the central processing unit. The screwing and unscrewing process is time-consuming, when the hard disk drive unit is removed from or placed into the portable computer.